Boom end fitting for sailboats



March 31, 1959 c. D. P. SMALLPEICE BOOM END FITTING FOR SAI-LBOA'TS 2Sheets-Sheet 1 Filed Oct. 31, 1955 FIG.2.

C D. P, 5MALLPf/(F March 31, 1959 c. P. SMALLPEICE 2,879,736

BOOM END FITTING FOR SAILBOATS Filed Oct. 31, 1955 2 Sheets-Sheet 2FIGB.

C. 1). R 5 MALI. PE/CE 2,879,736 BOOM END FITTING FOR SAILBOATS CosbyDonald Philipps Smallpeice,

Riddells Bay, Bermuda The invention relates to a boom end fitting suchas is used in sailing boats, for example, for spinnaker sails where itis desirable that the fitting for attaching one end of the boom to themast shall be the same as that on the other end of the boom forattaching the sail to the latter.

According to the invention the fitting includes one element of aspherical type joint, for releasable engagement with a coacting elementfast with the mast, and a means for attaching the sail to the boom, thejoint and the sail-attachment means being operable to their releasingpositions by the action of a single latch, or of a latch andwithdrawa-ble plunger respectively.

Preferably the joint element of the fitting is a cup, associated with alatch arrangement, for releasable engagement with a coacting ball fastwith the mast, and the sail-attachment means includes a withdrawableplunger to bridge a gap between a pair of jaws for holding an eye fastwith the sail.

Preferably, also, the latch arrangement of the fitting is biassed intoits engaging position, and also acts on the associated plunger for thebias to urge the said plunger into its bridging position.

In the case where there is one of the fittings at each end of a boom,each latch arrangement can be connected to be acted upon by 'a single,manual control which simultaneously operates the latch arrangement toits disengaging position and the associated plunger to its nonbridgingposition (although, of course, there may only be a need to operate thelatch arrangement at one end of the boom to disengaged position, and theplunger at the other end of the boom to its non-bridging position).

In the accompanying drawings:

Figure 1 is a diagrammatic plan view of a yacht hull showing the bottomedge of a spinnaker sail, set with the boom extending over the portside;

Figure 2 is an elevation, partly in section and with a central portionbroken away, of a spinnaker boom according to the invention, and afragment of an associated mast; and

Figure 3 is a section on line 3-3 of Figure 2.

Referring to Figure 1, the spinnaker boom 11 has identical end fittings12a, 12b of which the inboard one (i.e., 12a in the example shown) issupported from the mast 13 and the outboard one is attached to the portbottom corner of the sail 14, the bottom corners being sheeted at 15, 15to the hull 16 of the yacht. When it is desired to gybe, the end 12a ofthe boom is detached from the mast and connected to the starboard bottomcorner of the sail, while the end 12b of the boom is detached from theport bottom corner of the sail and connected to the mast.

The end fittings 12a and 12b are identical and, in the constructionshown in Figure 2, each includes a tapered socket l7 fitting over acorrespondingly tapered end of the main portion 11 of the boom andsuitably secured in position thereon. Integral with each socket 17 is an2,879,736 Patented Mar. 31, 1959 ice inverted spherical type ,orcup-like portion 18 which is to fit over a ball 19 fast with a bracket20 secured at 21, 21 to the mast 13. Adjacent the cup portion 18 is asubstantially Y-shaped latch-plate 22 which has its central limb pivotedat 23 in a housingformed by a transverse slot 24 in the region betweenthe socket 17 and the portion 18. This latch-plate has a forked upperend between the limbs 22a of which extends a plunger 25 which is guidedat one end by a screw plug 27 engaged in a bore of the fitting, and aspring 28 reacts between the plug 27 and an abutment 29 on the plunger25. U This abutment bears on the latch-plate for urging a nose 30 of thelatter into a position to obstruct the withdrawal of the cup 18 from theball 19, but not, in the particular construction shown, to contact theball 19.

Fast at the back of the cup 18 is a pair of jaws 31, 31a having alignedholes through which the plunger 25 extends to form a bridge forconfining an eye 32 fast with the sail. As shown at 25a, the outer endof the plunger 25 is of reduced diameter, and the hole in the jaw 31a isof corresponding size, whereby that jaw coacts with the step thus formedon the plunger for limiting outward movement of the latter under theinfluence of the spring 28.

Conveniently the limbs 22a of each latch-plate are united by a pin 33 towhich is secured a lanyard 34 passing through a hole in a bracket 35fast with the socket 17. In this way a pull on the lanyard 34 will turnthe nose 30 of the latch-plate 22 about a pivot 23 through approximately20, thus allowing socket 18 to be moved clear of the ball 19. The rearof the latchplate 22 acts on an abutment 29 fast on the pin 25 to movethe pin 25 against the bias of spring 28. The movement of the pin 25, inthis way, unbridges the jaws 31, 31a of cup 18. It will be understoodthat with the boom at any one setting the cup of one end fitting will beengaged with the ball 19, while the jaws 31, 31a and plunger 25 of theother end fitting will hold the sail. In other words the lanyards ofboth fittings will be operated in turn to effect the respectivedisengagements.

With the arrangement as shown in the drawings there is an end fitting,embodying the invention, at each end of the boom. The lanyard 34 can beemployed to simultaneously release the ball and cup joint and theplunger at each end of the boom. Thus, simultaneously, the boom isreleased from the mast, at one end of the boom, and the sail is releasedfrom the boom, at the other end of the boom, all in one movement.

What I claim as my invention and desire to secure by Letters Patent ofthe United States is:

1. A boom end fitting comprising a housing, the housing defining asocket for engagement over an end of a boom and one part of a two-partcup forming one element of a spherical type joint for releasableengagement with a ball member, another part of said cup pivotallymounted on said housing, resilient means biassing said other part of thetwo-part cup to a ball-engaging position, a pair of jaws on said housingand adapted to receive an eye fast with a sail which is to be used onconjunction with the boom, a withdrawable plunger bridging the gapbetween the jaws for holding the eye captive, said resilient biassingmeans also acting on said withdrawable plunger to hold it in agap-bridging position, and releasing means operatively connected to saidother part of said cup and also to said plunger to release the cup fromthe ball and the plunger from the jaws.

2. The combination of a boom; a fitting at each end of the boom, eachfitting comprising a housing, the houson said housing, resilient meansbiassing said other part ofthe two-part cup to a ball-engaging position,a pair of jaws on said housing and adapted to receive an eye fast with asail which is to be used in conjunction with the boom, a withdrawableplunger bridging the gap between the jaws for holding the eye captive,said resilient biassing means also acting on said withdrawable plungerto hold it in a gap-bridging position, and releasing means operativelyconnected to said other part of said cup and also to said plunger torelease the cup from the ball and the plunger from the jaws; and aninterconnection between the releasing means of the fittings at each endof the boom.

3. A boom end fitting comprising a housing defining a socket forengagement over an end of a boom, a cup on said housing and forming oneelement of a spherical 2,879,736 i p i type joint'for' releasableengagement with a ball member,

vresiliently biased latch means, for holding said element releasablyengaged with the. ball, a pair of jaws on said housing to receive an eyefast with a sail which is to be used in conjunction with the boom, aresiliently biased withdrawable plunger bridging the gap between saidjaws and for holding said eye captive, resilient biassing means "actingon said latch means and said plunger, and means operatively connected tosaid latch means and; to said plunger for releasing the cup from thebail member and the plunger'from the eye.

Larsen Nov/29, 1927 Plym p Mar. 30, 1954

